Present and future mobile phones include a multitude of antennas besides the cellular antennas, some of which do not need to be used all of the time. Besides the present BT and WLAN antennas, these include DVB-H (digital video broadcast—handheld), RF-ID (radio frequency identification), and UWB (ultra wide band) antennas, which are used only occasionally (for example, like when paying for tickets or watching a broadcast).
Antennas need a certain amount of space from other metallic objects within the device in order for them to radiate efficiently. This space is referred to as a backspace. Usually, the backspace needs to be metal free, and preferably plastics free. As a result of the backspace, although the antenna itself can be very thin, the total space required can be quite large, especially with DVB-H and RF-ID antennas. The backspace may not necessarily be an enclosed volume.
The listing or discussion of a prior-published document in this specification should not necessarily be taken as an acknowledgement that the document is part of the state of the art or is common general knowledge.